One faulty battery can burn through a bag. A cheap power bank can overheat while you sleep. A lithium polymer fire is one of the most serious battery accidents you could face. It doesn’t happen often, but when it does, it spreads quickly, fills the air with toxic smoke, and is almost impossible to stop once it starts.

The good news? With the right habits, you can avoid almost every accident linked to LiPo fires or rare cases of LiPo explosions. Whether you’re charging a phone or relying on a power bank for travel, here’s what you need to know to keep your devices safe.

In this blog:

• Are Lithium Polymer Batteries Flammable?
• What Causes Lithium Polymer Fire in Phones and Power Banks?
• Are LiPo Fires and LiPo Explosions Common?
• Warning Signs Your Battery Isn’t Safe
• What to Do If a Battery Starts Smoking or Explodes
• How to Prevent Lithium Polymer Fire (and Rare Explosions)
• Frequently Asked Questions

Let‘s get started!

Are Lithium Polymer Batteries Flammable?

Yes, but only under specific conditions. A lithium polymer battery can ignite if it’s overcharged, damaged, overheated, or short-circuited. When it burns, temperatures can exceed 1,000°C, and the smoke is highly toxic, which is why immediate action is critical.

What happens if a lithium battery catches fire?

Once a lithium battery ignites, it will burn until all stored energy is released. The fire can grow quickly, and in some cases, the sudden release of energy can lead to small explosions.

What Causes Lithium Polymer Fire in Phones and Power Banks?

A lithium polymer fire starts when the battery overheats and goes into thermal runaway, a chain reaction where heat builds faster than it can escape. Here’s what usually sets it off:

Overcharging or Faulty Charging

Using cheap or incompatible chargers, leaving devices plugged in overnight, or exceeding safe voltage levels can cause overheating. Many power bank and phone fires start with poor-quality charging circuits.

Physical Damage

A puncture or even a small dent can short-circuit the internal layers. Dropping your phone, crashing a drone, or crushing a power bank in your bag could trigger a fire hours later.

Aging and Internal Breakdown

Over time, LiPo batteries form tiny metallic growths called dendrites. These can pierce separators, causing internal shorts. Old or swollen batteries are more likely to fail.

Extreme Temperatures and Poor Storage

Leaving batteries inside hot cars, charging them near heat sources, or storing them fully charged for weeks stresses the cells and increases the risk of LiPo fires.

Are LiPo Fires and LiPo Explosions Common?

Not really. Most branded phones and power banks are built with safety circuits to prevent overcharging. But that doesn’t make them immune.

Most fires happen during charging, not while simply carrying or storing the device. And the biggest risks? Cheap, unregulated chargers and low-quality power banks. If you stick to trusted brands and follow basic care steps, the chance of a lithium polymer fire is extremely low.

Warning Signs Your Battery Isn’t Safe

Stop using your phone or power bank immediately if you notice:

• Swelling or bulging of the casing. This means gas is building up inside the battery due to internal chemical breakdown, which is often a precursor to thermal runaway.
• Heat even when it’s not charging. A healthy battery shouldn’t generate heat when idle. Unusual warmth signals an internal short or chemical reaction that can lead to a lithium polymer fire.
• A sharp chemical smell, like nail polish remover. That smell is from venting electrolyte, a sign that the battery casing may be compromised and the chemicals are breaking down.
• Hissing, popping, or crackling sounds. These sounds occur when pressure builds up inside the cell, sometimes just seconds before smoke, fire, or even a small explosion.

Moving the device to a fire-safe area (like a concrete floor or metal tray) is critical because once these symptoms appear, failure can escalate quickly.

What to Do If a Battery Starts Smoking or Explodes

If your phone or power bank begins to smoke, swell, or suddenly burst:

1. Move away immediately. When a lithium polymer battery explodes, it can shoot out hot metal fragments and burning electrolyte. Keeping a safe distance protects you from burns and toxic fumes.
2. Do not touch it. Wait until it stops burning or sparking. Even after the flames die down, the battery can still be extremely hot or reignite. Touching it too soon increases the risk of severe burns or chemical exposure.
3. Call emergency services if the fire spreads. Lithium fires can quickly ignite nearby objects and release toxic smoke, making them dangerous to fight without proper equipment.
4. If safe to do so, isolate it. Moving it onto a fireproof surface, like concrete or metal, helps prevent the fire from spreading. Tools like tongs or gloves protect you from direct contact.
5. Never throw it in the trash until it’s fully cooled and properly disposed of. Lithium batteries are considered hazardous waste. Tossing them in regular trash can start secondary fires in garbage bins or landfills.

How to Prevent Lithium Polymer Fire (and Rare Explosions)

Avoiding LiPo fires and the rare chance of LiPo explosions is simple if you build these habits into your routine:

1. Charge Safely

• • Use original or certified chargers only.
  • Avoid leaving devices plugged in for long hours or overnight.
  • Place phones and power banks on hard, flat surfaces while charging.
  • Never cover devices with blankets or stack items on them.

2. Store the Right Way

• • If you won’t use a power bank for weeks, keep it at around 50% charge instead of full.
  • Store it in a cool, dry spot away from sunlight or heat sources.
  • Don’t leave power banks inside cars on hot days.

2. Handle Problem Batteries and Emergencies

• • Unplug immediately if a device swells, smokes, or overheats.
  • Move it to a safe surface, preferably outdoors, on concrete or metal.
  • Smother flames correctly with sand or a Class D fire extinguisher. Never pour water; lithium reacts violently with it.
  • Keep your distance if it explodes, stay away until the sparking stops, and the battery cools completely.
  • Dispose of damaged batteries properly at a recycling or hazardous waste facility. Never throw them in regular trash.

Replace old or damaged power banks every 2–3 years or sooner if they show swelling, cracks, or unusual heat.

Frequently Asked Questions

What to do if a LiPo battery catches fire?

Leave the area immediately and contact emergency services. Do not attempt to put the fire out yourself; lithium polymer fires can spread fast and may reignite even after appearing to be extinguished.

What extinguisher is used for a lithium polymer battery fire?

A Class D fire extinguisher or an AVD (Aqueous Vermiculite Dispersion) extinguisher is recommended for lithium battery fires. For small fires, sand can help smother flames, but water should never be used.

How to properly maintain a LiPo battery?

Charge and discharge at moderate rates to minimize heat buildup. Avoid storing power banks fully charged, especially in warm environments, and keep them in cool, dry places to extend their lifespan and reduce risks.

Wrapping Up…

A lithium polymer fire can be devastating, but it’s almost always preventable. Most accidents linked to LiPo fires or rare LiPo explosions happen because of neglect, cheap chargers, old batteries, or careless charging habits.

The solution is simple: charge responsibly, store your power banks properly, and replace damaged or aging batteries before they fail. These small habits make a big difference.

Take care of your devices, and you’ll keep using them safely and confidently, without worrying about the dangers of a lithium polymer fire.

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